Head and Neck Quiz 1

Cranial Nerves and Facial Muscles

• The cranial nerve responsible for facial movement is the seventh cranial nerve, also known as the facial nerve.
• The muscle responsible for raising the eyebrows is the frontalis muscle.
• The muscle responsible for frowning is the procerus muscle.
• The muscle responsible for closing the eyelids is the orbicularis oculi muscle.
• The muscle responsible for wrinkles on the sides of the nose is the nasalis muscle.
• The muscle responsible for smiling excessively is the zygomaticus major muscle.
• The muscle responsible for wrinkles around the mouth is the orbicularis oris muscle.
• The muscle responsible for producing wrinkles or frown lines on the forehead is the frontalis muscle.

BOTOX and Facial Muscles

• The static pull of facial muscles on the skin produces wrinkles.
• BOTOX is used to relax facial muscles, reducing wrinkles and facial lines.
• The cranial nerve that innervates the facial muscles is the seventh cranial nerve.
• Injecting BOTOX at the lateral side of the orbicularis oculi muscle helps to reduce crow's feet.

Mechanisms of Action for Wrinkles

• The two mechanisms of action for wrinkles are dynamic wrinkles (from muscle movement) and static wrinkles (from skin elasticity loss).

Muscles of Mastication

• The muscle responsible for opening the jaw is the lateral pterygoid muscle.
• The muscle that inserts into the mandible and controls the jaw is the masseter muscle.
• The net action of the muscles of mastication is to facilitate chewing and jaw movement.

Salivary Glands

• The parotid glands produce the majority of stimulated saliva.
• The parotid glands are located in front of the ears.
• The Stensen's duct carries saliva from the parotid glands into the mouth.
• The submandibular glands produce the majority of unstimulated saliva.
• Wharton's duct is located in the submandibular glands.
• The viral infection that primarily affects the parotid glands is mumps.

Other Facial Muscles

• The orbicularis oris muscle is responsible for producing wrinkles around the mouth.
• The main cause of bunny lines on the nose is the contraction of the nasalis muscle.
• In cleft lip babies, the deformity of the Orbicularis Oris muscle is commonly observed.
• The levator labii superioris muscle is responsible for a gummy smile.
• The platysma muscle pulls the skin downward and forward, producing marionette's lines.
• The platysma muscle causes turkey gobbler neck.
• The muscles responsible for closing the jaw are the masseter and temporalis muscles.